docs: add simple example for network field

[googs1025]

• Fix docs: Add an example YAML file for the usage of the 'network' field. #548
  I would like to add a usage example of the network field in simple/example and demonstrate how to access each other between two pods. This will allow users to better understand the functions provided by the jobset itself.

[k8s-ci-robot]

Hi @googs1025. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[netlify]

✅ Deploy Preview for kubernetes-sigs-jobset ready!

Name	Link
🔨 Latest commit	e3d60a9
🔍 Latest deploy log	https://app.netlify.com/sites/kubernetes-sigs-jobset/deploys/6666ab40d415a70008695868
😎 Deploy Preview	https://deploy-preview-550--kubernetes-sigs-jobset.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[googs1025]

I'm not sure if we need to add documentation demonstrating how to ping between two pods.
like this

root@VM-0-4-ubuntu:/home/ubuntu# kubectl get pods
NAME                               READY   STATUS      RESTARTS   AGE
failure-policy-workers-0-0-c59sq   0/1     Completed   0          20h
failure-policy-workers-0-1-98htc   0/1     Completed   0          20h
network-jobset-leader-0-0-5dmv7    1/1     Running     0          20m
network-jobset-workers-0-0-g5n2t   1/1     Running     0          20m
network-jobset-workers-0-1-rghv6   1/1     Running     0          20m
paralleljobs-driver-0-0-dw5mh      0/1     Completed   0          20h
paralleljobs-workers-0-0-mfwtk     0/1     Completed   0          20h
paralleljobs-workers-0-1-5g6gp     0/1     Completed   0          20h
paralleljobs-workers-0-2-7n9j5     0/1     Completed   0          20h
paralleljobs-workers-0-3-vp8jc     0/1     Completed   0          20h
success-policy-leader-0-0-8rwff    0/1     Completed   0          45h
success-policy-workers-0-0-c58gl   0/1     Completed   0          45h
success-policy-workers-0-1-dhfq9   0/1     Completed   0          45h
root@VM-0-4-ubuntu:/home/ubuntu# kubectl exec -it network-jobset-leader-0-0-5dmv7 -- sh
/ # cat /etc/hosts
# Kubernetes-managed hosts file.
127.0.0.1	localhost
::1	localhost ip6-localhost ip6-loopback
fe00::0	ip6-localnet
fe00::0	ip6-mcastprefix
fe00::1	ip6-allnodes
fe00::2	ip6-allrouters
10.6.2.23	network-jobset-leader-0-0.network-jobset.default.svc.cluster.local	network-jobset-leader-0-0
/ # ping network-jobset-workers-0-1.network-jobset.default.svc.cluster.local
PING network-jobset-workers-0-1.network-jobset.default.svc.cluster.local (10.6.2.24): 56 data bytes
64 bytes from 10.6.2.24: seq=0 ttl=63 time=0.069 ms
64 bytes from 10.6.2.24: seq=1 ttl=63 time=0.062 ms
64 bytes from 10.6.2.24: seq=2 ttl=63 time=0.066 ms
^C
--- network-jobset-workers-0-1.network-jobset.default.svc.cluster.local ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 0.062/0.065/0.069 ms

[danielvegamyhre]

/ok-to-test

[danielvegamyhre]

left one comment

[danielvegamyhre]

Hmm I'm unsure if we want this network policy example in it's own folder, rather than in examples/simple. I guess you did this since you wanted to add a README explaining some extra steps the user can take to verify the pod-to-pod communication via pod hostnames is working correctly.

@kannon92 what do you think about this? The readme is a nice touch but I don't want the examples folder to get disorganized. Maybe we can think about each example having a short readme to accompany it like this?

[googs1025]

Hmm I'm unsure if we want this network policy example in it's own folder, rather than in examples/simple. I guess you did this since you wanted to add a README explaining some extra steps the user can take to verify the pod-to-pod communication via pod hostnames is working correctly.

@kannon92 what do you think about this? The readme is a nice touch but I don't want the examples folder to get disorganized. Maybe we can think about each example having a short readme to accompany it like this?

Yes, I separated them because I wanted to have a README.md document to describe .

[googs1025]

@danielvegamyhre @kannon92 After thinking for a while, I've decided to put it back into the examples/simple directory. How about this? I will move the README.md file to the Troubleshooting section here because network connectivity issues are something that users should be aware of. If users are unsure, they can refer to the Troubleshooting section for guidance.

[googs1025]

@danielvegamyhre /PTAL Any other suggestions or modifications? thanks!

[danielvegamyhre]

/lgtm
/approve

Thanks @googs1025!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: danielvegamyhre, googs1025

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [danielvegamyhre]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment